Controlling device



E. H. CLARK.

CONTROLLING DEVICE- APPLICATION FILED IULY 3.19 11.

Patented Mar. 23, 1920.

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CONTROLLING DEVICE.

E. H. CLARK. conmoume DEVICE.

APPLICATION FILED JULY 3 91?- 1,334,735. Patented Mar. 23, 1920.

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E. H. CLARK. CONTROLLING DEVICE.

APPLICATION FILED JULY 3.1911.

Patented Mar. 23, 1920.

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CONTROLLING DEVICE. APPUCATION FILED JULY 3,1911.

Patented Mar. 23, 1920.

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CONTROLLING DEVICE.

APPLICATION FILED JULY 3,1911.

Patented Mar. 23,1920.

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EDGAR H. CLARK, GENEW YORK, N. Y., ASSIGNQR T0 WE$TERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

CONTROLLING DEVICE.

Speciflcation of Letters Patent.

Application filed July}, 1917. Serial 110. 178,468.

To. all. whom it may concern:

' Be itknown that I, Enoan H. CLARK, a citizem of the United States, esiding at New. York in the county OfNE-Vt York and State of New-York, have invented certain new and useful Improvements in Controlling Devices, ofwhich the following is a full, clear, concise, and exact, description.

Thisv invention relates to signaling systems and more particularly to controlling deviceseinployed in telephone systems.

The present invention has for its purpose the provision of a switching system responsive to impulses of various characteristics transmitted from adistant point, said system operating to selectively control, the operation ofautornatic devices.

Other features not specifically pointed out will appear from the detailed description and appended claims.

The drawings, when arranged in accord ance with the, chart indicated in Figure 8, diaglviammatically represent a-portion of a telephone systei-n employing the present invention.

In the system herein disclosed the apparatus associated with an A operators osition of a semi-automaticexchange an the apparatusassociated with the B operators position of a manual ofiice are shown. It will be understood that only those parts are shown which are necessary for describing the establishment of a desired connection from a calling subscriber at A to the jack of a party line B.

In. the present system the sequence switches are of the type disclosed in the patent to Revnolds and Baldwin 1,127,808, and are similar in operation and function tothose disclosed in the patent to McBei-tv, 1.125.579.

The selective switches of this system may be of the tvne disclosed, in patent to Craft and Reynolds 1.123.696. The operating circuits for these switches are shown in the patcnt to Lundell 1,168,319.

In the present disclosure register. control ling devices and actuating relays are employed. The operation of these devices. except in so far as they are necessary for a lear understanding of this invention, has not been described. This operation is fully de cribed in the above-mentioned patent to Lnndcll 1,168.319.

It is believed that the invention will host tive ringing current is applied;to the called.

line.

When the calling subscriber removes his receiver from the switchhook, the :line relay.

102 -is actuated in tlie Well-known. manner to hghtthe, lamp 103, The operator, 9;; 101;?

Patented Mar. 23, 1920. i

ing the lighting of lamp 103-, inserts plug 104 t in jack 105 of'the; calling line. A circuit is thereupon completed from grounded bats tcry, winding-of cut-off relay 1 06, sleeveof jack 105,- sleeve of plug 104:, windingof relay 107. to ground. The relays 1 06and 10.7: are

energized overthis circuit. The cut-ofi' relay 106 attracts its armatures to disconnect the line relay 102 from the calling line, and the line relay in turn extinguishes lamp 103. The relay 107, on attracting its armature, completes a circuit from ground, frontoon: tact and armature of relay 10.7, contact 108, magnet of sequence switch 100, to grounded battery, tomove the sequence switch, into position 2. As soon as the sequence switch 100 reaches position 2, a circuit is completed from grounded battery, magnet of sequence switch 200, contact 202, conductor 203, con:

tact 109 to ground, to move the sequence switch 200 into position 2. In position 2 of sequence switch 200, an energlzingr circuit For tho up-drive magnet 204 is closed from grounded battery winding of the l p-drive magnet 204, contact 205, left-hand back contact and armature of relay 206 to ground. The up-drive magnet 204 controls the elevation of the cord finder generally designated 207 As soon as the brush 208 of the cord finder 207 engages terminal 209 associatcd with the cord circuit which has been connected to the calling line, the relay 206 is energized over a circuit which may be traced from grounded battery, windingof relay 206. contact 210, brush 208, terminal 209, conductor 211, contact 110, to ground. Relay 206 attracts its armatures and at its left-hand armature interrupts the operating circuit of the lip-drive magnet 204. which circuit was previously described and at the right-hand armature and'front contact of relay 206 a locking circuit is established for this relay from grounded battery, Winding of relay 206, contact 291; right-hand armsture and front contact of relay 206, brush 212, terminal 213, conductor 214, contact 111, to ground, which maintains the relay 206 energized until the selector sequence switch 100 has moved out of position 11. At the left-hand armature and front contact of relay 206 a circuit is closed from ground, contact 215, magnet of sequence switch 200 to grounded battery, to move this sequence switch into position 3.

The operator thereu on places her headset (not shown) in te ephonic communication with the substation apparatus and ascertains from the calling subscriber the number of the desired line. The operator then sets up this number on her key set, which is shown in Fig. 4 of the drawings. As soon as the operator has depressed the keys K, K?, K, K, K and K, corresponding tothe designation of the desired party, operating'circuits for the registers 400, 40], 402,403, 404 and 405 are completed. These registersthen rotate to ositions indicated by the depressed keys of thekcy set. The operating" circuit for the register 400 extendsffroin grounded' battery, magnet of the "register 400, right-hand armature and back'contact of stoprelay 406, conductor '407,'c,ontact 221, to ground. The operating circuits for the registers 401, 402, 403, 404 and 405 are similarly traced through the right-hand armature and back contact of the stop relays 408, 409, 410, 411 and 412,

respectively, conductor 407, to ground at contact 221. As soon as the stop relays 406, 408, 409, 410, 411 and 412 are energized, a circuit is completed from round through the left-hand armature an front contacts of these relays, conductor 413, contact 222, magnet of sequence switch 200 to grounded battery, to move the sequence switch out of position 3. Under the control of its master contact223', sequence switch 200 rotates into position'6; I I

'Thefundamental circuit is now established from grounded battery, winding of the line relay 112, contact 113, conductor 114, terminal 216, brush 217. conductor 218, outer, left-hand armature and back contact of the upper zero counting relay 219, winding of the stepping r'elay 220, contact 224., brush 225, terminal 226, conductor 227 contact 115 to ground. Relay 112 attracts its armature and thereby completes a locking circuit for itself. At the left-hand front contact and armature of relay 112 a circuit is also completed to move sequence switch 100 into position 3. With the sequence switch 100 in position 3 and with the line relay 112 energized, an operating circuit for the up-drive magnet 116 is completed from grounded battery. winding of magnet 116, conductor 117, contact 118, left-hand armature and front contact of relay 112 to ground. Under the control of the np-drive magnet, a selector switch, generally designated 119, elevates its brushes and also elevates its commutator brushes 120 and 121. Each time that the commutator brush 120 encounters a conducting segment 122 of commutator 126, a circuit in shunt of the fundamental circuit just described is completed from ground, commutator brush 120, conducting segment 122, contacts 123 and 160, right-hand armature and front contact of relay 112, winding of the line relay 112 to grounded battery, to short-circuit the steppin relay 220 in the well-known manner. T is short-circuiting operation of the stepping relay continues until the upper zero counting relay 219 of the chain of relays, the length of which is determined by the setting of the district register 400, is actuated. When the relay 219 attracts its armatures, at its outer armature and back contact it interrupts the fundamental circuit above described, and at its inner armature and front contact completes a circuit from ground, contact 228, magnet of sequence switch 200, to grounded battery, to move the sequence switch outof position 6 into position 7.

When the fundamental circuit was interrupted at the upper zero countiir relay 219, the line relay 112 deenergized an at its left hand back contact and armature completed a circuit from ground, contact, 124, magnet of sequence switch 100 to grounded battery, to move this sequence switch out of position 3. Under the control of its master contact 101, sequence switch 100 continues to rotate until it reaches position 6. In position 6 of the sequence switch 100, an energizing circuit for test relay 125 is closed from grounded battery lower winding of relay 125, contact 127 to ground. The test relay 125 attracts its armatures and at its lower armature and front contact completes a circuit from ground through contact 128, magnet of sequence switch 100 to grounded battery, to move this sequence switch into position 7. In position 7 the test relay 125 IS maintained energized over a circuit which may be traced from grounded battery, upper winding of the test relay, upper front contact and armature of relay 125, test brush 129 of the selector 119 to ground, over the test terminals of busy trunk lines. With the test relay 125 energized, an operating circuit for the up-drive ma 1 net 116 is again completed from grounded attery, winding of the magnet 116, conductor 117, contact 130, lower front contact and armature of relay 125 to ground. As soon as the test brush 129 of the selector 119 encounters the test terminal of an idle line, which idle condition will be indicated by the absence of ground on the test terminal, the test relay 125 deenergizes and thereby completes a driving-circuit for driving the sequence switch 100 out of position 7. This circuit may -be traced from grounded battery, imagnet of sequence switch 100, contact 131, lower 1ba'ck contactv and armature of test relay 125,

unded battery,;magnet' of'sequence: switch 1 number '-1indicating fimpulses, 73S wvi'llflbe 229, contacts 230, 231, to ground. 30H.

1 With 'thez'sequence switch; 100 in position -11 an"d the siequenceswitch200 in position 7 acircnit is-completed :fron -grounded bat-- tery, right-hand winding-of relay- .02, lefthand armature and back contactkot relay 30,3, con'ductor304, re eating-coil305 lower inner warmaturegand hack contact of i ,rclay 301,: conductor 137 of then-trunk, terminalF-134, brush 135, contact 7136, conductor 227', terminal 226, a brush 4 225, contact 1 233, contact 234, winding ofirelay 235, to ground. The relays 235 and 302 are energized 7 over this circuitnnd attract;theirfarniaturesi At the ifront'contac't l and armature oil-the relay 235 a circuit is corn leted-froin ground, contact:236, magneto .sequence switch 229 to grounded battery, to ;Inove the sequence switch 229. out --of position 2. into .position .3.

lUpon'theenergization of the relay:302, a circuit is completed for lighting lamp 306 after the calling line hasbeen extended to theoperators position. The actuating circnit fof lamp 306maybe traced from grounded battery, conductor 307, armature and front'contact of relay. 302, conductor 308, outermost back contact and armature of relayn309,'resistance 310 to ground. The operator,'on notingithe lighting of lamp 306, depresses the key 311, whereupon a circuit is completedgfrorn ground, winding of -relay 301, key 311, conductor-312, winding of slow releasing relay 2, to grounded battery. The relays 2-and 301 are energized over this oncuit and attract their armaturesh The relay 2 in: itsarmature and frontcontactapplies ground to various controlling leads shown in Fig. 5. 1

\Vhenthe relay 301 attracted its armatures the controlling circuit of the relay 235, which is extended over conductor 313, was open at the left-hand armature and front contact of relay 10. The relay 235 denergi'zes and at its back contact and armature completes a circuit from ground through contact 237, magnet of sequence switch 239, to grounded battery. The sequence switch 239 rotates out of position 3 'and continues torotate through its various positions back to position 1 under'the control of its master contact 238.

After relay 301 attracted its armatures and while sequence switch 239 is moving throu h vpositions 3% to 4, a circuit was establis ed fronr grounded battery, winding of the relays 6 and 5, conductor 314:, inner front contact and mpper; armature of relay 301, condnctor,-138,' terminal 139, brush 132, contact-.133," conductori'114, terminal 216, brush 217, ."conductor 218,'contact ;232, to ground. Then impulse transmitted in this last gde'scribed circuit may be termed a, fpickup impulse and serves'to'place the impulse recording -device in: condition to receive; the

pointed out.v

The 5 operation of the relays? and 81 and the operation of the: switching relays 13,. 15, 29, 18, 31, 19 and 33, which aretcontrolled by the relays 7 and 8, may. described; as -f ollows :=In response to the %pick-up impulse the relay 6 .is-.-cnergized rand Zat zitslrighbhand front contact and ar-maturecompletes a circuit traceable frombatter-y, righthand or "holding=--windi'11g ofTthe relay 7,

winding -'of relay 8, left hand back icontact and armature: of; :relay '7; i ,Irighthand front contact and I armature fofi relay :6, to. "ground over conductor'fQ. .Thedelay '8 attracts wits armatures and at its right-hand armature. and "front contact completes "fii cilcllit from ground, back eontact,: armatu're and: winding of relay '10, to agrounded battery; =The. relay 10 attracts its armaturesandestablisheswalocking circuit 'for iitsel'fcwhiclr-is completed from grounded battery-, 'winding of relay 10,

right-hand armature rand -contact spring 11 of this relay, left hand' baclccontacts and armature of'relay $17 to ground over conductor 3. -At its left-hand frontcontact-and arma" ture; the relay '8" prepares a' circuit forrenergizin'g the left 'hand :or1pull up i-winiding-of the relay -7. This 'last inentionedwinding, however, is short circuited as-long as the relay '6 maintains its-urrnatures attracted in response to "the i'pick-u'p impulse. "At :the

close of the I licit-up" impulse both windings of the relay E7 are energized over-a. circuit traceable from grounded battery, right-hand winding of relay '7, winding-of relay- 8, lefthand winding of relay 7-,left hand front contact and'a'rmature of relay 8, to ground over couductori). At'this'timethe stations switching relay 13 has its-energizing-circuit completed at the right-hand front 1 contact and armature of relay Twas will be more fully described. In response to the'stationsat this time and retracts its armatures. At the close of the stations impulses the armatures of both relays 6 and 12 will be attracted and the relay 7 will be deenergized to complete at its right-hand armature and back contact a circuit for the thousands switching relay 15. In response to thethousands impulses either the relay 6 or the relay 12 will be operated, whereupon the cycle of operationof the'relays 7 and 8 will begin again. In other words, the relay 8 will be energized over a circuit now traceable from grounded battery, right-hand'winding of relay 7, winding of relay 8, left-hand back contact and armature of relay 7, through the right-hand front contact and armature of relay 6 or the leftrhand armature and back contact of relay 12, to ground over conduc tor 9. "The relay 8 attracts its armatures and when the thousands series of impulses has terminated and the relays 6 and 12 are inert, the circuit for the'left-hand or pull-up winding of relay :7 will be from grounded battery, right-hand winding of relay 7, winding ofrelay 8,-left-handwinding of relay 7, lefthand' front contact and armature of relay 8 to ground over conductor 9. "lVith the'armatures of the'relay 7 attracted a circuit is completed at the right hand front contact of relay 7 for energizing the switching relay 29. In response to the thousands and hundreds translation impulses, the relays 6 and 12 will be operated again and a circuit will be completed from grounded battery through the right-hand winding 'of relay 7 left-hand front contact and armature of relay 7, through the right-hand front contact of relay 6, or the left-hand front contact and armature of relay 12, to ground over conductor 9. This operation serves to shortcircuit relay 8. At the close of this series of impulses the circuit holding winding of relay 7 is interrupted either at the armature and contact of relay 6 or at the armature and contact of relay 12.: At the right-hand back contact and armature of relay 7 an energizing circuit for the hundreds switching relay 18 is completed. The cycle of operation I of the relays 7 and 8 will be completed for the relays 31, 19 and 33. At the end of the hundreds series of impulses the relay 7 will be energized to complete a circuit for the tens switching relay 31; at the end of the tens series of impulses the relay 7 will-be deenergized to complete a circuit for the tens and units translation switching relay 19; and at the end of the tens and units translation series of impulses the relay 7 will be energized to complete a circuit for the units switching relay 33.

As soon as the relay 7 attracted its armatures in response to the pick-up impulse, a circuit was completed for energizing a station switching relay 13. This circuit is completed from grounded battery, winding of relay 13, armature and back contact of- 35, 36, 37, 38 39, 40, conductors 41,9. and:

3toground, n

When the sequence switch 229 reach'ed position 4 a circuit was completed from grounded battery, magnet of sequence switch 200, contacts 270 and 271 to ground to move this sequence-switch into position 8. While. the sequence switch 229 is rotating through its various positions in proper sequence, .it

closes its contacts (shown-at the right-hand.-

corner of Fig-'2) to control the transmission of the impulses which cause the-automatic.

selection ofthe proper ringing current ofthe desiredsubscriber'on the party line; and

also transmits impulses ifor actuatingi the z proper; group of relays which control the setting up of the indication of the desiredsubscribers number. The character ofthese impulses is controlled by the length 013010 sure of the contacts of sequence switch 229. lmpulses of three different characters may be transmittedover thevtip and ring eonductors of the selected trunk. These'impulses may be described as being long, short and medium in length. For convenience,

the long impulse may be said to consist of early, middle and late closure of the contacts leading to the tip or ring conductors. The short impulse may consist either of an early, middle or a late closure of these contacts; while the medium length impulse may consist of an early and a middle closure, or a middle and a late closure of these contacts. For convenience in describing the selection of ringing current, for the actuation of the relays which control the setting up of the desired subscribers number, the terms early, middle and late will be used to describe the character of the impulse employed in these operations.

Let it be assumed that the desired subscribers number is 9987-W. Under this assumption the operator in setting up the number on the keyboard has caused the thousands register 401 to stop in position 9, the hundreds register 402 in position 9, the tens register 4:03 in position 8, the units register 404 in position 7 and the stations register 405 in position 4. In order to select the proper ringing current for ringing party W, it is necemary to lock up the relays 21, 22 and 28 of Fig. 5. To accomplish this, it is necessary to transmit the following code impulses: a middle impulse uses-235 on-the tip conductor, and early, middle and late-impulses on the ring conductor. With thisisetting' ofthestations register 405 *while the sequence switch 229 is rotating through positions 421053;, a circuit is completedfrom ground, contact 239, conductor 240, contacti41 5, conductor 416, contacts 241, 233, brush-.225, terminal 226'; conductor227', contact-1313, b'l'ilSh- 13 5,j=terminal 134, ring conduster-"137, lo werhinner armature and front ofwrelay i301; :conduct'om .313, leftthrough position 5- to 51-, a circuit is closed from groundg'contact 242, conductor 243,

contact 4:17, conductor 418,-contact' 244; con-I ductor'218; brush 217, terminal 216, conductor -114; contact:"133,:-brush 132; terminal 139,1;ip' conductor 138', upper innerarmature and front contact of relay 301 conductor 314,-windings of relays 5- and' 6, toigrounded battery. While the sequence switclr229 is passing: through position 5 10151}, a cirruit-is closed fromgroun'd, contact: 245, conductor2sfi 'conta'ct 419, conductor 416, con- 241 and-233, brush 225,terminal:-226,

' conductor 227, contact 136, brush 135,terminal 134, conductor 137, inner lower armature and front contact of relay 301, conduc- -.=tor 313:, leeEt-hand front contact and armature ofrelay- 10, winding of relay 12, to-

I grounded battery.

It will thus be seen that: the first stations' impulse sent is transmitted over the ring conductor to energize the relay 12. With the relay 1 2' energized, an energizingcircuit is completed for the relay 21. which in part controls the: lighting of the stations lamp. This: relay grounded battery, right-hand winding of relay- 21-, right-hand back contact andarmature of'relay-22, conductor 23, oute-rlefthand armaturerand contact ofrelay- 13, conductors'24andi25, back contact and lefthand armature of relay 6, righbhand front contact and armature of relay 12, conductor 91, to ground at the armature of relay 2. Relay 21fattracts its armature and at its inner left-hand front contact and armature establishes a locking circuit for itself through both of its windings in series to ground over conductorv 9. In response to the middle impulses, the rela s5, (Sand 12 are energized. With these re ays energized, the relay 22 1s ope-rated over a circuit traceable from grounded battery, right-hand is energized from' from grounded batterythrough both w-indmgs; m serie ofi'this relay, its: inner lefthand: front contact and: armature, conductors 9 and3 to ground at the armature; of relay 2. In response to'the 13.136111113111565 the relay 12 is energized" andthereby:completes an energizin circuit for -the' relay 28 whichexten'dsonn undedibattery, right-hanid winding of t is-relay,' righthand from contact and armature of relay tact andarmature of relay 13, conductors 24'an'd 25, left liand back contact and armature ofi relay 6, right-hand Efront" contact and armature of relay 12,- conductors 9 and 3, to' round at the armature-bf" relay 2. The re ay 28 attracts its armaturesand establishes a locking circuit for itself through both windings in" series, its inner deft-hand front-contact and armature,'- over condimtorsQ-and' 3, to "ground! At the close 'of this series of impulses, the relays 6 'and '12 are denergizedwhich interrupts thehold- 'ing circuit of the relay -7, permitting this 'relay" itoretract" its armatures. It Wlll' be remembered as soon as the relay13attracted its armatures, a break 'point in the Series circuit' for relays 14 and 15 was closed.

l/Vhen now relay 7 retracts its' armatu'res at the close of the series of impulses, the

energizing circuit for re1ay+14 is completed from; grounded battery winding of relay "14, winding of'relay 15, inner right hand front contact and armature of the relay 13, inner right-handback contact and armature of relay 29, conductor 30,' inner'righthand back contact and armature of relay 31, conductor 32, inner right-hand backcontact and armature of relay33," conductor 34, right-hand back contact and armature of relay 7', to ground over the conductor 3. The relays'14'and'15 are energized in this circuit. The relay 14 at its armature and back contact interrupts the original energizing circuit of the relay 13. The relay 15 at its inner left-hand armature and spring 35 interrupts the locking circuit of relay 13 and also completes a locking circuit for itself traceable from grounded battery, windings of relay 14 and 15 in series','inner left-hand armature and contact spring 35 of relay '15, contact and contact springs 36, 37, 38, '39, 40, conductors -11, 9 and 3 to g ound. It will be understood that the relay 15 also closes a break point in the circuit for transmitting the thousands series of impulses to the relays controlling the lighting of the thousands lamps.

It has not been deemed necessary to describe the transmission of the impulses for operating theNo. 9 thousands lamp.- It is believed that it will be understood that with the thousands impulse regist'ers'et in position 9 that the following code impulses-will be sent: a middle impulse over the tip con? ductor, and an early, middle and late impulse over the ring conductor. In response to an early impulse over the ring conductor the relay 12 is energized to complete a circuit from ground, conductors 3 and 9, right- .hand-armature and front contact of relay 12, left-hand armature and contact of relay 6, conductor 25, outer right-hand armature and front contact of relay 15, conductor 520,

left-hand winding of relay a, outer armature and aba'ck contact. of relay 0, to grounded battery: The relay a is energized in this circuit and establishes a 7 locking 1 circuit for itself which may be traced from grounded battery, outer contact and armature of relay 0, both windings of relay a in series, right-hand inner front contact and armature of relay a, conductor 539, conductor 3', to ground; While the middle impulses are being=transmitted, the relays 5, 6 and 12 are energized; With these relays ener- .gized 'a circuit is completed-from ground,

conductors 3 and 9, right-hand armature and front contact of relay 12, armature and front contact'of relay 5, conductor 27, outer front contactofrelay 0 to grounded battery.

The relay 6 attracts its armatures and completes a locking circuit for itself from I grounded battery, outer left-hand armature and back contact of relay 0, both windings of relay b in series, right-hand inner front contact and armature of relay 1) to ground over conductor 539, as previously described. In response to the late impulse, only the relay 12 isfenergized. This completes a circuit from ground over the conductors 3 and 9, right-hand armature and front contact of relay 12, left-hand armature and back contract of relay 6, outer' right-hand contact and armature of relay 15, conductor 520, outer left-hand armature and front contact of relay 6, left-hand winding of relay c, to grounded battery. Relay 0 attracts its armaturesand thereby establishes a locking circuit for itself and also interrupts the holding circuits of relays a and b.

At the Iclose of the thousands series of impulses the relays 5, 6 and 12 deenergize and the relays 7 and 8 become energized. With relay 7 energized a circuit is completed from grounded battery, windings of relays 14 and 29 in series, inner right-hand front contact and armature of relay 15, conductor 16, inner right-hand armature and back contact of relay 18, inner right-hand back contact and armature of relay 19, ri ht-hand front contact and armature of relay 7, conductor 3 to ground. Relays 14 and 29 are then maintained energized in a series circuit from grounded battery, inner left-hand armature and contact springs 36 of relay 29, contacts and contact springs 36,

, left-hand armature and front contact of relay 15, conductor: 525, left-hand winding of relay b, outer left-hand armature andlays in Fig. 7. At the close of this series of 38, 39, 40, conductors -11, 9 and 3 to ground. The relay 29, by attracting its armatures, controls-the transmissionof the impulses controlling the translation at the relays efi'ectin the thousands and hundreds :numher-indicating lamps.

The thousands impulses which have just been transmitted have been suflicient to select the thousands lamps 8 and 9. It is now necessary to transmit impulses to select the v No. 9 lamp. By notin the code shown on Fig. 7 itwill be seen 1; at since the number 9 is an odd number, and it occurs in the second five hundred'ofthe odd thousands, an early, middle and late impulse will 30 be sent over the tip conductor, and a middle impulse over the ring conductor of the selected trunk. These impulses are :transmitted in accordance with the translation which takes place, asWiILbe-indicated by tracing the following circuits. w

In response to theearly impulse of the series controlling --the 'tho'usandsihanslation, only the relays 5 and 6 are energized, and since.the.relayz12$is hot ienergized go neither the relays di forzbt will .be:enecgiz'ed. But in response tothe tuiddleirnpulse the relays 5,6 and 12 :wilL-be energizedy-and since the relay 29 is already energized, a-circuit is completed from ground, conductors 5 3 and 9, right-hand armature and frontoontact of; relay 12, armature and front contact of relay 5, outer ri ht-hand armature and front contact of; relay 29, conductor 527, winding of relay 6*, to grounded battery. The relay 2; attracts its armatures and completes a locking circuit from grounded battery, windings of relay' 6 in series, inner right-hand front contact andarmature of relay 5?, to ground over conductor 539, as described. In response to the late impulse, only the relays 5 and 6 are energized. For this reason no further energizing circuit is completed for the thousands controlling "reimpulses the relay 7 deiinergizes. This completes an energizing circuit for the relay 18 extending from grounded battery, winding of the relay 14, winding of relay 18, inner right-hand front contact and armature of relay 29, conductor 30, inner back contact and armature of relay 31, conductor 32; in-

ner right-hand back contact and armature of relay 33, conductor 34, armature and back contact of relay 7, conductor 3,to ground. 12o Relay 18 by attracting its arlnatures causes the deenergization of relay 29 and establishes a locking circuit for relays 1i and 18 through contact springs 38, 39 and 40, conductors 41, 9 and 3 to ground. For selecting the No. 9 hundreds lamp. the middle impulse is transmitted over the tip conductor and an early, middle and late impulse over the ring conductor of the trunk selected. It is not deemed necessary to trace 130 circuits in which these impulses are transmitted through the contacts of sequence switch 229. It will he assumed that these various impulses are transmitted to actuate the relays 5 and 6' and 12. Since an early impulse is first transmitted or'er the ring conductor, only the relay 12 will be energized, as a result of which an energizing cir' cuit is completed from ground, at the armature and contact of relay 2, conductors 3' and 9, right-hand armature and front contact of relay 12, armature and back contact of relay 6, conductor 25, outer right-hand armature and front contact of relay 18, conductor 529, left-hand Winding of relay or, outer lefthand armature and back contact of relay 0, to grounded battery. Relay (1 attracts its armatur'es and locks itself up to ground over conductor 539. The middle impulse is then transmitted over both the tip and ring conductors, as a result of whichthe relays 5, 6 and 12 are energized. This completes a circuit from ground over conductors. 3 and 9, right-hand armature and front contact of relay12,.arnurture and front contact ofrelay 5', conductor 27, outer left-hand armature and front contact of relay 18, conductor 53].

Jeft hand winding of relay b outer lefthand armature and backcontact of relay (2. to grounded battery. Relay 5 locks itself up to ground over conductor During .the transmission of the late impulses, only a late impulse is transmitted over the ring conductor, thus only the relay 12 is energized. This relay, by attracting its armu ture, closes an energizing circuit from ground, over conductors 3 and 9, right-hand front contact and armature of relay 12, lefthand armature and back contact of relay ('3. conductor 25, outer right-hand armature and front contact of relay 18, conductor 5%. outer left-hand armature and front of relay 1), left-hand winding of relay c, to groundedbattery. The relay 0 is energised in this circuit and attracts its armatures and at its outer left-hand back contact and armature interrupts the energizing circuits of relays n and b. The relay in operating, attracts its armatures and completes a holding circuit for itself over the conductor 539. At the close. of this series of impulses, the relay 7 is energized and a. circuit is completed for the relay 31 which controls the transmissionof impulses to. the relays which light the tens lamp. The relay 31 is energized over a circuit which is traceable from grounded battery, windings of relays 14 and 3]. inner right-hand front contact and armature of relay l8, inner right-hand armature and back contact of relay 1!). conductor 20. righthand front contact and armature of relay 7, to ground over conductor 3. Relay 31 attracts its armatures and at contact spring 38. breaks the holding circuit of the actuated relays preceding it in the series and looks itself to ground througlisprings 38, 39 and 40,- over conductors 41',- 9 and3;

For selecting theNo; 8 tens lamp, a middle impulse is transmitted over the tip conductor, and an early, middle and late impulse over the ring conductor of the selected trunk. Since an early impulse is transmitted over the rin conductor and no early impulse is transmitted over the ti conductor, relay 12 is energized and the re ays 5 and 6 remain deenergized. Under these conditions a circuit is closed extendin from ground over conductors 3 and- 9, rig t hanii armature and front contact of relay 12, lefthand armature and back contact of relay 6, conductor 25, outer left-hand armature and front contact of relay 31, conductor 533, left-handwinding of relay'A"; outer left; hand armature of relay 0 ,110 grounded battery. The relay A locks itselfto ound ever conductor 539. The middlev impulses are then transmittedoverthe tip and" ring conductors to energize the relays 5, 6 and12. lVi'th this combination of relays actuated, a circuit is closed from mind over conductors?) and 9', right-han armature and front contact of relay 12, armature and front contact of relay 5, conductor 27, outerrighthand armature and front contact of relay 31, conductor 535, left-hand winding of re lay B outer left-hand armature and. back contact of relay (3 to grounded battery. The relay B locks itself to ground. over conductor 539. A late im ulse is now transmitted over the ring conc uctor, but no late impulse is transmitted over the tip conductor of the selected trunk. Relay 12 is energized, but relays 5 and 6 are inert. Under these conditions a circuit is closed from ground over conductors 3 and 9, right-hand armature and front contact of relay 12, lefthand armature ancbback contact of relay 6, conductor 25, outer left-hand armature and front contact of relay 31, conductor 533, outer left-hand armature and front contact of relay B left-hand windinu of relay C to grounded battery. The re ay C attracts its armature and at its outer left-hand armature and back contact interrupts the holding circuit of the relays A and B The relay C" in operating also closes a locking circuit for itself. The last mentioned impulses are sufficient to select the Nos. 8 and 9 tens lamps. At the close of this series of impulses the relay 7 retracts its armatures and thereby com letcs a circuit for energizing relay 19. his circuit extends from grounded battery, windin of relays 14 and 19 in series, inner rightand front contact and armature of relay 31, conductor 32. inner right-hand front contact and armature of relay 33, conductor 34, right-hand back contact and armature of relay 7. to ground over conductor 3. Relay l9 by attracting its armatures-interrupts the holding circuit of relay 31 and establishes a locking circuit for itself. through contacts 39 and 40, conductors 41, 9 and 3 to ground.

It is now necessary to transmit impulses to select the No. 8 tens lamp. Since the numoral 8 is in the second group of even tens, it is necessary to transmit an early and a middle impulse over the tip conductor, and

- a middle and late impulse over the ring conestablishes a locking circuit for itself to ground over 539. In response to the late impulse, the relay 12 is energized, which in turn controls the ener izationof the relay A -over a circuit traceaile from ground over conductors 3 and 9, right-hand armature and front contact of relay 12, left-hand armature and back contact of relay 6, conductor 25, outer right-hand armature and front contact of relay 19, conductor 575, winding of relay A to grounded battery. The relay A attracts its armatures and establishes a locking circuit for itself over conductor 539.

Since the relay 7 remains energized at the close of the last series of impulses, an energizing circuit is completed from grounded battery, windings of relays 14 and 33, inner right-hand front contact and armature of relay 19, conductor 20, right-hand front contact and armature of relay 7 to ground over conductor 3. The relay 33 attracts its armature and establishes a locking circuit for itself through its inner armature and contact spring 40 to ground over conductor 41.

For selecting the units lamp No. 7, an early, middle and late impulse is transmitted over the tip conductor, and a middle impulse over the ring conductor. Since no early or late impulses are transmitted over the ring conductor, the relay 12 is not energized and therefore completes no energizing circuit for operating the relays controlling the lighting of the units lamps. However, middle impulses are transmitted over the tip and ring conductors to energize the relays 5, 6 and 12. Under these conditions a circuit is closed from ground over the conductors 3 and 9. right-hand armature and front contact of relay 12, armature and front contact of relay 5, conductor 27, outer righthand armature and front contact of relay 33. conductor 580. left-hand winding of relay B outer left-hand armature and back contact of relay (1, to grounded battery. Relay B attracts its armatures and thereby establishes a locking circuit for itself over conductor 539.

As soon as the relay 18 attracted its armatures a circuit was completed for energizing the relay 42; and this relay by attracting its armatures completes circuits for lighting the various number-indicating lamps. The relay 42 is initially energized over a circuit extended from grounded battery, left-hand winding of this relay, inner right-hand front contact and armature of the relay 18, inner right-hand back contact and armature of the relay 19, conductor 20, right-hand front contact and armatureof relay 7, conductor 3 to ground. The relay 42 when once energized maintains itself actuated through its right-hand winding through resistance 57 9 to ground over conductors 9 and 3, and when relay 33 attracts its armatures the relays 17, 44 and 45 are energized in parallel over circuits traceable from ounded battery to the windings of these rei iys through the inner right-hand front contact and armature of relay 33, conductor 34, right-hand back contact and armature of relay 7 to ground over conductor 3. It will thus be seen that the thousands and hundreds lamps are simultaneously lighted and that at a subsequent point the tens, units and stations lamps are lighted. The circuit for lighting the No. 9 thousands lamp may be traced from grounded battery, inner right-hand armature and contact of relay 42, conductor 542, outer lefthand armature and back contact of relay a inner left-hand armature and back contact of relay 7), outer right-handarmature and back contact of relay a, inner left-hand armature and front contact of relay 0, through the No. 9 thousands lamp, outer right-hand front contact and armature of relay- 0, conductor 543 to ground at the outer leftrhand contact and armature of relay 42 to ground. The circuit for lighting the No. 9 hundreds lamp is completed from grounded battery. outer right-hand armature and front contact of relay 42, conductor 546 through the No. 9 hundreds lamp, inner left-hand front contact and armature of relay 0', outer righthand back contact and armature of relay a, inner left-hand back contact and armature of b, inner right-hand front contact and armature of relay b conductor 539 to ground.

It will be remembered that the following relays of Fig. 6, controlling the lighting of the tens and units indicating lamps, have been actuated and locked up, 0 A, B and B With these relays actuated, a circuit is closed for lighting the No. 8 tens lamp: this circuit is traceable from grounded. battery. right-hand armature and contact of relay 45. conductor 548. through the No. 8 tens lamp. inner left-hand front contact and armature of relay C outer right-hand back contactandarmature of relay A inner left-hand back contact and arn'iature of relay Bf, inner ri ht-hand front contact and armature of relay A conductor 539 to ground. The circuit for lightin 'the No. 7 units lamp extends from groun ed battery, right-hand armature and contact of relay -15, conductor 550, lzimpxNo. 7, inner left;- hand armatureandback contact of relay A, inner left-hand armature and front contact of relay B, inner right-hand front contact and armature of relay-B conductor539 to round;

he circuit for lighting the stations lamp; extends from grounded battery, righthand armature of relay 44 and. contact 46, stations lamp lV, right-hand front contact and armatureof relay 28, outer left-hand front contact and armature of relay 21, outer left-hand front contact and armature of relay 22, left-hand front contact and armature of relay 17 to ground over conductor 3.

When sequence switch 229 returns to position 1 after rotating through its various positions-to'transmit the code impulses, a circuit is completed for moving the sequence switch'100 out of position 11 andinto 'osition 16. This circuit may be traced from ground, contacts 276' and 275, brush 274,

contact 273, contact 150, magnet of sequence switch 100, to grounded battery. The sequence switch 100, by rotating to position 16, closes'its contacts 175 and 176 to close breakpoints in the conversationalcircuit. As soon'as the sequence switch 100 rotates out of" position 11, the relay 206, whose locking circuitwas completed at the contact 111, retracts its armatures. At the left hand armature and back contact of relay 206, acircuit is'completed from ground through contact 260, magnet of sequence switch200, to grounded battery. The sequence switch 200 rotates'into position 18 in which position a circuit is completed for down-drive magnet 261, from grounded battery, winding of the magnet, contact 262, to ground. Under the control of the downdrive magnet, the cord selector 207 restores to its' normal position. When this takes place, a circuit is closed from ground, contacts' 264 and 263, winding of motor magnet of the sequence switch 200, to grounded battery. This circuit moves the sequence switch into its normal position.

The operator, on noticing the number of the desired line set up on the call indicating lamps, inserts a plug 316 into the jack 317 of the party line over which the desired subscriber can be reached and releases key 311. The release of this key causes the restoration of the number indicating apparatus and also causes the dei nergization of the relay 301. Relays 300 and 302 become energized and attract their armatures. As

soon asthe plug-316 is inserted into the jack 317, a circuit is' completed from grounded battery, through thej lamp 306, winding of the relays309, 318,.slecve of plug 316. sleeve of jack 317', windiiigpf re.- lay 319, to ground. The relays 309 and 318 attract theinarmatures, It willjbe understood that the lamp 306 is shunted at this time. As soon as the relay 309 attracts its armaturesa circuit is prepared for therelay 320, which extends from grounded battery, winding of tlie relay ,32,0, armature and back contact of ,relay321, back contact and armature ,of relay 322, outer left-hand front contact and armature, of relay 309, conductor 308, armature and contact of re: lay 302, to ground through relays 309, 318 and 319. The relay 320 is energlzed inthis circuit and attracts its armatures. Simultaneously with the" energizationf of ..the:relay 320, the relay 303 is actuated-.over: a circuit traceable from. grounded battery, winding of; relay 303, inner armature and front contaca-of relay 309,. resistance 310, to ground. The relay 303'attifacts its armatures. The relays 323 and 324- wet-cactuated as soon as the relays controllingthe stations lamps were operated. The relay 323 was energized over a circuit closed from grounded battery, winding-of rela 323, conductor 325, the lower armature an front contact of relay 301, conductor 326, resist-. ance 551, right-hand front contact and armature of relay 28, outer left-hand front contact and armature of relay 21,;ou'ter lefthand front contact and armature of relay 22, armature of relay 17 toground. The relay 324 is energized over a circuit coinpleted from groundedfbattery,winding of relay 324, conductor 327, outer upper armature and front contact of relay 301, conductor 328, outer left-hand front contact and armature of relay 21, outer left-hand front contact and armature of relay 22, left-hand front contact and armature of relay 17 to 110 ground over conductor 3. These relays, as soon as they were energized, were locked up through contact spring 329, conductor 523, resistance 522, conductor 3 to ground. .\s soon as the relay 303 attracted its arma- 115 turcs the following locking circuits were substituted for the circuits previously traced for the relays 323 and 324. The locking circuit of relay 323 is traceable from grounded battery, winding of relay 323, 12c left-hand armature and front contact of this relay, contact 329, ri ht-hand armature and front contact of relay 303, to ground. The locking circuit of the relay 321 extends from grounded battery, wind- 12.5 ing of relay 324, right-hand armatures and front contact of relay 324, contact spring 329, armature of the relay 303, to ground.

In order to prevent the ringin of a substation set other than that of t e desired 130 party, when the plug 316 is being inserted into jack 317, an interrupting device 330 is provided. This interrupter is of the wellknown type which consists of a constantly rotating shaft on which are secured the disks 331, 332 and 333. The disks 332 and 333 are insulated from the shaft on which they are secured and are provided with brushes which engage their peripheries. The periphery of the disk 331, with the exception of a very small portion, is covered with an insulating material. The conducting portion is so positioned with respect to the conducting portions of the disks 332 and 333 that while a circuit is completed through the disk 331, no circuit is completed through the disks 332 and 333. The purpose of this adjustment will be hereinafter described.

After the insertion of the plug 316 into the jack 317 and after the energization of the relay 318, as soon as the brush of the disk 331 encounters its conducting segment, a circuit is completed from grounded battery through the disk 331 and its brush, through the contact and contact spring 331, through the winding of the relay 335, lower armature 'of the relay 318, contact spring 336, right-hand contact and armature of relay 32-1, to ground at contact spring 329 and armature of relay 303. The relay 335 attracts its armature and completes a circuit from grounded battery through the ccntact sprin 334, over the circuit just described. When now the brush of the disk 323 encounters its conducting segment, a circuit is completed from the positive source of ringing current 337, conducting portion and brush of disk 332, left-hand winding of the relay 322, right-hand front contact and armature of relay 323, left-hand front contact and armature of relay 335. upper front contact and armature of relay 320, upper armature and upper contact of relay 318, tip of plug 316, tip of jack 317, through the substation apparatus of the desired subscriber, ring of jack ring of the plug, lower armature and front contact of the relay 320, left-hand armature and front contact of relay 324 to ground.

The relay 322 is marginal and does not attract its armature-s until the called subscriber has answered. When the relay 322 is energized, the relay 321, which was shunted, attracts its armatures and completes a circuit from grounded battery, lefthand armature and front contact and winding of the relay 321, outer left-hand front contact and armature of relay 309, armature and front contact of relay 302, windings of the relays 309, 318 and 319, to ground. The relay 321 looks itself up in this circuit and prevents the reapplication of ringing curren When at the close of the conversation the A operator restores the selector switch 119, after noting the replacement of the receiver on the switchhook of the calling station, the supervisory lamp 306 operates in the well-known manner to inform the B operator that the call has terminated, whereupon she removes plug 316 from jack 317 to denergize the relays 3'09, 318, and 319. The relay 309, in de'einergizing, causes the deenergization of relay 303, and this relay interrupts the locking circuit of the relays 323, 324 and 335. Relay 338 is provided to prevent a second series of impulses from actuating the call-indicating apparatus until the B operator has removed the plug 316 from the jack 317.

When the B operator noted the number indicated she released key 311, which causes the relays 301 and 2 to denergize. Relay 301, on retracting its armatures, extends the trunk conductors 137 and 138 to the called substation. Relay 2 on retractin its armatures removes ground from con uctor 3 to restore the actuated relays of the relay indicating device.

At the termination of the conversation the actuation of the supervisory relays 170 and 171 operates in the well-known manner to inform the A operator that the call has terminated. She thereupon removes the plug 1041 from the jack 105, which causes the relays 106 and 107 to retract their armatures. This completes a circuit for moving the sequence switch 100 out of position 16 and into position 18. This circuit may be traced from grounded battery, winding of magnet of sequence switch 100, contact 140, armature and back contact of relay 107. In position 18 the down-drive magnet 1 11 is operated in the well-known manner to restore the selector switch 119 to its normal position. When the switch is restored, a circuit is completed from ground, commutator brush 121, segment 1452, contact 144, magnet of sequence switch 100. to grounded battery to move this sequence switch into its normal position; After the restoration of the select r 119, the lamp 306 which was previously shunted, is lighted and the B operator removes plug 316 from the jack 317 of the called line. This operation restores the apparatus associated with the B operators position, to its normal position.

What is claimed is:

1. An apparatus for counting series of current impulses comprising a series of electromechanisms, means for supplying series of current impulses. means for operating the first electromechanism of the series, means effecting the energization of each electromcchanism of the series in succession in response to a series of impulses, means operative upon the energization of any electromechanism for deenergizing the relay of the the energization of certain relays for indipreceding electromechanism of the series, and other means operable upon the energization of a particular electromechanism.

2. In a counting device, a series of relays, means for supplying current impulses to control saidrelays, means for operating the first relayof the series, means effecting the energization of each relay of the series in succession in response to said impulses, means operative .upon the energization of any relay for deenergizing the preceding series, and means operable upon eating the number of impulses transmitted.

3. A-selection-controlling apparatus comprising a-series of electromechanisms, means for supplying series of current impulses to control said electromechanisms, means for energizing a particular electromechanism of the series inresponse to a Series of im ulses, said electromechanisms thereafter eac 1 controlling the energization of a succeeding and.

effectingthe dener ization of a preceding electromechanismwot the series, and mechanismefiective uponthe energization of a predetermined electromechanism to bring about certain circuit changes in the apparatus to he controlled.

4. A controlling apparatus comprising a series of successively cooperating electromechanisms, means for supplying series of current impulses to control the same, means for energizing a particular electromechanism in response to a series of impulses, each of said electromechanisms thereafter upon energization operating to denergize a preceding electromechanism of the series, and circuit-controlling means operable upon the energization of a certain one of the electromechanisms.

5. In a controlling system, an incoming circuit, controlling means governed over said inconiin circuit, a plurality of outgoing-circuits, a fiurality of switchingmeans for controlling said outgoing circuits, devices for controlling said switching means including three electromagnetic windings arranged in series, the first electromagnetic winding b its cuergizatiou controlling the cucrgizatiou of the scrond electromagnetic winding, the second electromagnetic winding by its euergization controlling the cnergizalion of the third electromagnetic winding and effecting the deiinergization of the first electromagnetic winding.

6. A controlling apparatus comprising a series of successively coiiperating electromechanisms, a holding circuit for said electromechanisms having break points controlled by each of said electromechanisms, means for supplying series of current impulses to control said electromechanisms, means for energizing a particular electro mechanism, each of said electromechanisms thereafter upon energization operating to said series interrupt said holding circuit, and circuit controlling means operable upon the energnation of a certain one of the electromechanisms.

T. In a controlling system, means for sup plying series of currentimpulses, an incoming circuit, a plurality of outgoing circuits, a series of electromechanisms arranged to be successively operated to control said outgoingeircuits, circuit controlling means responsivefto series of current impulses, said circuit, controlling means when operated serving to cause theenergizationof one electromechanism of the series, and when inoperative serving to cause the energization of a succeeding electromechanism of the series.

8. In a controlling system, an incoming circuit, means for supplying series of current impulses over said circuit, a plurality of outgoing circuits, and a seriesofelectrom'echanisms for controlling said outgoing circuits, controlling means operating in response to series ofimpulses to control said electromechanisms, said controlling means when operated controllingthe actuation of an electromechanism of the series, a succeed ing electromechanism ofthe seriesbeingactuated under the joint control of said controlling means and said actuated electromechanism.

9. In combination, series of impulses of a chain of switching sponsive to said series ating said relays.

10. In combination, means for producing! series of impulses of various characteristics,

a chain of switching relays arranged to be actuated in succession, and means responsive 105 to said series of impulses for actuating said switching relays.

11. In combination, means for producing series of impulses of various characteristics,

a chain of switching relays arranged to be 110 actuated in succession, means responsive to of impulses for actuating said switching relays, indicating devices, and means operating under the control of said switching pulses of the series for operating said indicating device.

12 In combination, means for producing series of impulses, a chain of switching relays arranged to "be actuated in succession, 120 means responsive to said series of impulses for actuating said relays, a plurality of indicating devices, means operating under the control of said switching relays and in response to the impulses of the series to oper- 125 ate said indicating devices in succession.

13. In combination, means for producing series of impulses of various characteristics, a number-indicating device, switching mechanisms for operating said indicating 9 means for producing various characteristics, relays, and means reof impulses for acturelays and in response to the im- 15 i device having operating circuits, said switching mechanisms being selectively operated in response to the impulses of a series, and switching relays for controlling said operating circuits, said switching relays being operated in response to series of impulses.

14. In combination, three electromagnetic windings, a circuit normally including two of said windings in series, a second series circuit including said three windings in series, means controlled in part by one of said windings for completing said second series circuit, means controlled in part by a second winding for afiecting the de'encrgization of said first winding and for maintaining said third winding energized, and circuits controlled by said windings.

15. In combination, three electromagnetic windings, means for energizing one of said windings, a series circuit including said windings and controlled by said first winding, means controlled in part by a second winding for maintaining a third winding energized and for deenergizing the first winding, and circuits controlled by said windings.

16. In combination, three electromagnetic windings, means for energizing one of said windings, a series circuit including said windings and controlled by said first winding, means controlled in part by a second winding for maintaining a third winding energized and for denergizing the first winding, and a series of electromechanisms arranged to be successively actuated under the control of said third windin 17. In combination with three electromagnetic windings controlled by impulses of current from a distant point, means to first actuate one winding, means then operative to simultaneously energize three windings, means then operative to deenergize the first and second of said windings and to maintain said third winding energized, and means then operative to de'nergize said third winding, and a series of electromechanisms arranged to be operated in sequence under the control of said electro-magnetic windings, and means to actuate two of said electromechanisms in response tothe operation of said electro-magnetic windings.

In witness whereof, I hereuntosubscribe my name this th day of June A. "D. 1917.

EDGAR H. CLARK. 

